The increasing network and the increasingly stringent requirements for data transmission even in the private domestic field are leading to use of optical cables. In addition to regional distribution, the so-called last mile is also becoming increasingly important, where an optical cable connects a distribution station to individual buildings or dwellings. In this case, the primary factor is to use special cables which can be used without any additional measures both within a building and outside a building since this avoids spliced joints or plug connections which are susceptible to faults. So-called “drop cables” such as these can be laid inside and outside buildings, and outside the ground or else as underground cables there.
Cables with different application ranges such as these are intended to satisfy a multiplicity of requirements. On the one hand, the cable should be as light and small as possible in order to allow it to be laid and processed further without any difficulties. Furthermore, it should have as tight a bending radius as possible in order also to be laid with a bending radius of down to 20 mm within buildings. Because of the use of these cables within buildings, the materials used must comply with the appropriate fire protection regulations. Furthermore, it should be possible for the cables to be already provided with plug connectors, in order to speed up the installation process, as prefabricated cable.
A cable such as this for the stated application ranges is subject to widely differing environmental influences. In particular, the resultant temperature differences between a heated building and the outdoor area, which may be considerably cooler, leads to different expansion of the optical cable, as a result of which the optical fiber may be subject to tension loads. One reason for this is the different materials from which a cable such as this is formed. Their expansion behavior can lead indirectly to a change in the attenuation, thus possibly adversely affecting the data transmission rate. In the worst case, for example, the optical fiber can be drawn off completely in the area of a plug connection.